1. Getting started – choosing the right system

With composting, there is no ‘one size fits all’. There are a range of considerations to be taken into account when choosing which composting system is right for you at home. This can include what type and size of garden or outdoor space you have, the amount and type of waste you produce, cost, and the amount of time you have available.

The main types of systems are detailed in the following table.

## Comparing different types of composting systems

| | Garden Compost bin | Compost Heap | Green Johanna specialist composter | Green Cone food waste digester | Kitchen (Bokashi) Composter | Wormery | |----------------------|--------------------|--------------|-----------------------------------|-------------------------------|-----------------------------|---------| | **Size** | Various sizes | As big or small as you make the pile! | 330 litres | Underground chamber 80 litres | Usually around 18 litres and sold in pairs to allow continual composting | Various sizes | | **Overview** | Handles garden and uncooked food waste such as vegetable peelings. Produces easily harvestable compost. | Home built system. Handles garden and uncooked food waste such as vegetable peelings. Produces easily harvestable compost. | Handles garden and cooked/uncooked food waste (including meat, fish and dairy). Produces easily harvestable compost. | Handles cooked/uncooked food waste (including meat, fish and dairy). Solar heated cone circulates warm air and breaks down food waste in a digestion chamber below ground. | A small indoor composter, ideal for use in the kitchen, for all cooked food (including meat, fish and dairy). Two units allow continual composting. | Uses worms to break down organic food waste matter. Produces compost and liquid fertilizer. | | **Suits households with** | - a fair amount of garden waste and uncooked food waste such as vegetable peelings - a garden needing compost - a food digester to deal with other food waste | - a garden needing compost - a food digester to deal with other food waste | - up to 5 or 6 people - quite a lot of food waste - some garden waste - a garden that requires compost - space for a large container | - up to 4 people - a fair amount of food waste - an existing Garden Compost bin or Heap - a sunny garden with space for installation | - a small to medium amount of food waste - a use for compost - limited garden space, OR - need for indoor compost production, but facilities to finish the process outside | - a medium amount of food waste (excluding meat, fish and large amounts of citrus fruits) - a use for a liquid plant feed - limited outdoor space | | **Advantages** | - takes garden waste and some uncooked food waste - does not need good drainage - does not attract vermin - easy to install - easy to get hold of | - takes garden waste and some uncooked food waste - does not need good drainage - no cost (do not need to buy a unit) - easy to set up | - takes cooked and uncooked food - also takes garden waste (30% of volume) - can be placed on any free draining surface - does not attract vermin | - takes cooked and uncooked food - minimal residue (but does not produce compost) - does not attract vermin - residue feeds nearby plants | - takes cooked and uncooked food - fast process and small and compact - does not smell or attract vermin/flies - does not require installation - produces liquid plant feed | - takes some cooked and uncooked food - small, compact and flexible - can be used indoors and outdoors - does not smell or attract vermin/flies - does not require installation - produces high quality compost | | **Considerations** | - requires turning or stirring - compost must be harvested | - requires turning - compost to be harvested | - requires stirring with stick provided - compost must be harvested - requires shady conditions | - does not take garden waste - needs free draining soil and a sunny spot - requires some effort to install (hole needs digging) - no compost to harvest - requires bacterial activator | - requires activating bran (ongoing cost) - does not take garden waste - after two weeks contents need to be buried or put in traditional Garden Compost bin or Heap | - does not take garden waste - requires some attention - must be kept cool - compost must be harvested | | **Outlets** | Garden centres and online | n/a | Online | Online | Online | Online |

See our separate Suppliers list for details of outlets. 2. Getting Going - What to put in your composter or food waste digester, plus techniques and tips for getting the best results

**Composting cooked and uncooked food waste**

Food digesters such as Green Johanna, Green Cone, Kitchen (Bokashi) Composter or Wormery

You can put in such things as cooked vegetables, dairy products, fruit skins, vegetable peelings, tea bags, coffee grounds and eggshells. All except a Wormery will also take meat, fish, bones and citrus peel. A Green Cone can also accept small amounts of dog waste. A Green Johanna needs around 30% garden waste as well.

**Composting garden waste and uncooked food waste**

Garden Compost bins or a home built Compost Heap

As well as garden waste, these take uncooked food waste such as fruit and vegetable matter but not usually meat, fish or dairy products. However, if these items have been in a Kitchen (Bokashi) Composter for 2 weeks, they can then safely go into a Garden Compost bin or Heap. A Garden Compost bin or Heap is a mini eco-system, with microscopic organisms doing all the hard work and the key is giving them the right balance of ‘green’ (nitrogen containing) and ‘brown’ (carbon containing) ingredients; usually a 50/50 ratio. Once you have begun to make compost, if you find nothing much is happening, it is likely that your mixture or the moisture content are not quite right.

**Getting the right mix of ingredients**

**Green ingredients include:** vegetable peelings, fruit waste, old flowers and bedding plants, hedge clippings, young annual weeds, tea bags, coffee grounds, garden prunings and grass cuttings.

**Brown ingredients include:** cardboard (torn up), egg boxes, scrunched up/shredded paper, loo roll tubes, fallen leaves, straw and hay, crushed eggshells, vacuum dust, bedding and sawdust from vegetarian pets, hair, wood ash, wood shavings, wool and natural fibres (torn up).

**Getting the right moisture levels**

**Too wet:** moist, sappy materials such as grass cuttings and vegetable peelings add moisture and break down quickly, but on their own become wet and smelly. They need tougher, drier ‘brown’ items to balance the mixture. These are slower to rot, but create air pockets, and allow mini-beasts, such as worms, room to move around. Also, it may help to move the bin or heap into a more sunny position or add air by sticking a broom handle (or aerator) into the compost and wiggling it, or dig the contents over with a garden fork. Too dry: if the mix is too dry, (often caused by dry, brown leaves and prunings in autumn), increase the amount of ‘greens’ and add water using a watering can or leave the lid off when it rains. Alternatively, materials may be too big to break down and need to be chopped up into smaller bits.

The wrong stuff Whatever composter or digester system you have, the following items should not be put in: diseased plants, plants infected with club root, droppings from meat eating animals, cat litter, nappies, perennial weeds (such as dandelion or thistle), glossy paper (such as magazines), coal and coke ash and synthetic fibres. If it doesn’t rot – it can’t be composted! Non-bio-degradeable items such as plastic bottles, glass and metal, should be recycled through your kerbside recycling scheme or at a local recycling site. 3. Getting Results – Commonly asked questions and useful hints and tips

I have a lot of flies These are fruit flies and are common and harmless. To prevent them, cover materials waiting to be composted with newspaper or a lid. When adding them to a composter, cover them with a layer of soil, grass cuttings or cardboard. Alternatively try leaving the lid off overnight or bury new ingredients below the surface.

I have seen evidence of rats If you live near water, farmland, open countryside or derelict buildings, you are likely to already have rats visiting your garden. You can discourage rats by taking some simple steps: • rats don’t like disturbance - tap the Garden Compost bin or Heap when you pass • rats like dry environments, so keep your compost moist • rats don’t like crossing open spaces - site the composter away from walls or fences that provide a sheltered ‘runway’ • if your garden compost bin is open underneath, put thick wire mesh under the bottom to prevent rats getting in

Can I compost rose prunings/leaves? It is not recommended as some rose diseases (especially black spot) survive the composting process and could re-infect new roses.

What about poisonous plants, evergreen shrubs (such as leylandii) or rhubarb tops? Although poisonous when growing, these can be composted as the toxins break down during the composting process. If you have large quantities of evergreen clippings, compost them by putting them in a heap, adding ‘green’ materials (such as grass clippings) and water well. Leave for 6-12 months and use as a mulch around established trees and shrubs.

Can I put all my grass cuttings in the Garden Compost bin or Heap? Grass cuttings are fine but too many will cause a problem as they ‘slump’ and exclude air. They are also rich in nitrogen and heat up as they rot making the material wet, smelly and slimy. Try mixing them with more fibrous ‘brown’ materials (such as torn up cardboard, straw or scrunched up paper) which add air pockets and balance nitrogen levels. Alternatively, store them in the sun to dry off and add them gradually over time.

Can I put weeds in? Weeds can go in, but avoid perennial weeds which can re-grow. Also avoid annual weeds which have gone to seed, as the seeds can germinate when you use the compost. A good way to get rid of perennial weeds such as nettles, couch grass, dock or bindweed, is to chop them up and leave them in a tied bin liner in the sun until they get hot and go brown and sludgy. Or, put them in a bucket of water with the lid on and add them to a composter when they have decomposed.

**What if I have too much green waste to fit in my composter?** Start a Compost Heap. Chop the green waste up as small as you can and leave it on the ground in a pile in your garden. The decomposition process will begin, and you can add it bit by bit to your composter when you have room or keep it as a home built Compost Heap. If you still have too much, you can take it to your local household waste recycling site or use a garden waste kerbside collection service, if available.

**Can I compost all my autumn leaves?** Autumn leaves take a long time to compost. Small amounts are all right, but it is best to compost the rest separately in loosely tied plastic sacks, well watered, with plenty of holes or in a ‘leaf-mould’ container with 4 posts surrounded by chicken wire.

**How will I know when my compost is ready?**

- A Garden Compost bin takes approximately 6-9 months. Compost at the bottom should be dark brown in colour with a spongy, soil-like texture.
- A home built Compost Heap takes approximately 6-9 months.
- A Green Johanna will produce its first batch of compost in approximately six months, and every 3-4 months thereafter.
- A Green Cone unit will not produce compost.
- With a Kitchen (Bokashi) Composter the resulting materials can be buried in soil, or placed in a Garden Compost bin or Heap after 2 weeks.
- A Wormery will produce a dark liquid fertilizer every few days and also produces a small amount of rich compost (worm casts) after 6-12 months.

**Why does it smell bad?**

- A Garden Compost bin or Heap may need turning or stirring. Also mix in some carbon-rich material like torn-up cardboard.
- The Green Johanna will smell of ammonia if not enough ‘brown’ carbon-rich material is added. Add some torn-up paper or card and mix the contents well with the stirring stick.
- The Green Cone is a sealed unit and when set up properly emits no smells.
- Using a Kitchen (Bokashi) Composter is an odour free process.
- If your Wormery starts to smell, you have overfed the worms or put in too much of one type of material or it is lacking in air. You can help by putting rubber gloves on and stirring up any uneaten food as this allows the oxygen to penetrate.